ACTG A5047 is designed to: 1) Investigate the effect of 2 of the HIV-1 protease inhibitors ritonavir and saquinavir on the PK's of HMG-COA reductase inhibitors used to treat hyperlipidimia, and 2) evaluate the effect of one of these HMG-COA reductase inhibitors on another protease inhibitor nelfinavir.